摘要：As a new type of adsorption material,biocharhas become a hotspot in the environmental field suchas soil remediation and enhancement of carbonstorage.However,little attention has been given torelationship between the deceased heavy metalbioavailability and the changes in soil humuscomposition with biochar addition.Inthisexperiment,a pot experiment was conducted toapply different proportions of biochar (0%,0.5%,1%,2%and 5%) to cadmium (Cd) -contaminatedsoil,and the soil physical and chemical properties,humiccomponents,availablecdand Cdconcentration in wheat were determined.Resultsshowed that soil pH and soil organic matter (SOM)was significantly increased and the DGT-Cd wassignificantly decreased under all biochar treatments,with 5% biochar addition had the greatest impact.The content of fulvic acid (FA) and humin (HM) insoil increased with the increase of biochar addition,while the content of humic acid (HA) showed adecrease trend with the application of biochar.TheCd concentration in wheat roots,stems and grainswas significantly negatively correlated with soil pH,HM,SOM and FA content,but positively with soilavailable cadmium (DGT-Cd) and HA.The resultsdemonstrated that biochar caneffectivelyimmobilize heavy metals,thereby increasing soilpH,changing the humus component,and reducingheavy metal bioavailability in contaminated soils.
